Target

To identify the actual length of problematic piles in the Palace basement in order to

clarify the reasons for the foundation geometry violation and possible relation of the foundation integrity violation to local zones of permafrost thawing.

Results

Actual pile length was measured, varying from 3.32 to 4.69 m.

A fragment of the pile foundation, limited by ‘problem’ piles, is located above the area having a sharp drop in depth (3.5 to 6 m) along the boundary of overcompacted soils along the GPR profile length.

Local partially frozen/partially thawed zones up to 1-2 m in size were registered.

Explicit filtration flows of ground melt waters were not registered.

The complicated structure of the covering frozen ground massif above the rock causes uneven distribution of the building foundation piles bearing capacity.

Value

Determining the actual position of piles, monitoring the state of the foundation, composed of frozen soils.